Pitt, who is speaking out about his red carpet scare. He was attending the premiere for "Maleficent" when he was accosted, forced to fend off a man who was trying to grab him. ABC's Linzie Janis has the story. Good morning, Linzie. Reporter: Good morning. Brad Pitt is describing the scary moment prankster vitalli sediuk grabbed him. He has a warning for sediuk. This morning, brad Pitt is speaking out about the chaotic moment he was accosted on the red carpet last Wednesday. Pitt, who can be seen in this video, briefly fighting back against vitalli sediuk, describes the reporter as a, quote, a nutter. Telling "People" magazine, I saw someone stage diving over the barrier at me. He says sediuk latched on to his lapel. I cracked him twice in the back of the head. Not too hard but enough to get his attention because he did let go. There was a scuffle. And the gentleman was quickly escorted away from the red carpet with security. Reporter: Sediuk pleading no contest to battery and unlawful activity at an entertainment event. Maintains he just wanted to give him a hug. I never punched. I never slapped brad Pitt in the face. This is false information. What the hell is your problem, buddy? Reporter: But the 25-year-old has built a career around pranking celebrities in public places. Like will smith, Bradley cooper, Leonardo Dicaprio and Adele. And was reportedly fired from a television station, after crawling under America Ferrera's dress at last year's Cannes film festival. I don't like an exhibitionist. But he's going to spoil it for the fans who have waited up all night for a photograph. And he should know, if he tries to look up a woman's dress again, he's going to get stomped. Sediuk pleaded no contest to battery and unlawful activity. The Ukrainian has been sentenced to three years probation with one year psychiatric counseling. And he's been ordered to stay away from brad Pitt and Angelina Jolie. He says his future stunts will be done legally and in a polite way. Good for brad Pitt sticking up for America. You don't go looking up girls' dresses. Don't go anywhere near a red carpet.

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